diff --git a/vertx-core/src/main/java/io/vertx/core/impl/future/CompositeFutureImpl.java b/vertx-core/src/main/java/io/vertx/core/impl/future/CompositeFutureImpl.java
index 9053ec00d54..779769c9953 100644
--- a/vertx-core/src/main/java/io/vertx/core/impl/future/CompositeFutureImpl.java
+++ b/vertx-core/src/main/java/io/vertx/core/impl/future/CompositeFutureImpl.java
@@ -61,8 +61,12 @@ private CompositeFutureImpl(int op, boolean initializing, Future<?>... results)
 
   private void init() {
     for (Future<?> result : results) {
-      FutureBase internal = (FutureBase<?>) result;
-      internal.addListener(this);
+      if (result instanceof FutureBase) {
+        FutureBase internal = (FutureBase<?>) result;
+        internal.addListener(this);
+      } else {
+        result.onComplete(this);
+      }
     }
     Object o;
     synchronized (this) {
@@ -205,8 +209,10 @@ public int size() {
 
   private void doComplete(Object result) {
     for (Future<?> r : results) {
-      FutureBase internal = (FutureBase<?>) r;
-      internal.removeListener(this);
+      if (r instanceof FutureBase) {
+        FutureBase internal = (FutureBase<?>) r;
+        internal.removeListener(this);
+      }
     }
     if (result == this) {
       tryComplete(this);
diff --git a/vertx-core/src/test/java/io/vertx/tests/future/CompositeFutureTest.java b/vertx-core/src/test/java/io/vertx/tests/future/CompositeFutureTest.java
index 08b8056266d..e40b5b8b75e 100644
--- a/vertx-core/src/test/java/io/vertx/tests/future/CompositeFutureTest.java
+++ b/vertx-core/src/test/java/io/vertx/tests/future/CompositeFutureTest.java
@@ -11,15 +11,9 @@
 
 package io.vertx.tests.future;
 
-import static org.assertj.core.api.Assertions.assertThatThrownBy;
-
-import io.vertx.core.Completable;
-import io.vertx.core.CompositeFuture;
-import io.vertx.core.Future;
-import io.vertx.core.Promise;
+import io.vertx.core.*;
 import io.vertx.core.impl.future.FutureImpl;
 import io.vertx.test.core.Repeat;
-
 import org.assertj.core.api.ThrowableAssert.ThrowingCallable;
 import org.junit.Test;
 
@@ -29,13 +23,12 @@
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
-import java.util.function.BiConsumer;
-import java.util.function.BiFunction;
-import java.util.function.Consumer;
-import java.util.function.Function;
+import java.util.function.*;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
 /**
  * @author <a href="mailto:julien@julienviet.com">Julien Viet</a>
  */
@@ -577,4 +570,103 @@ public void testAnyRemovesListeners2() {
     Future.any(f, Future.succeededFuture());
     assertEquals(Collections.emptySet(), f.listeners);
   }
+
+  @Test
+  public void testCustomFuture() {
+    Promise<Void> p1 = Promise.promise();
+    Promise<Void> p2 = Promise.promise();
+    Promise<Void> p3 = Promise.promise();
+
+    CompositeFuture cf = Future.all(p1.future(), new MyFuture(p2), p3.future());
+
+    p1.complete(null);
+    p2.complete(null);
+    p3.complete(null);
+
+    assertTrue(cf.isComplete());
+  }
+
+  private static class MyFuture implements Future<Void> {
+
+    private final Future<Void> delegate;
+
+    private MyFuture(Promise<Void> promise) {
+      delegate = promise.future();
+    }
+
+    @Override
+    public boolean isComplete() {
+      return delegate.isComplete();
+    }
+
+    @Override
+    public Future<Void> onComplete(Handler<AsyncResult<Void>> handler) {
+      return delegate.onComplete(handler);
+    }
+
+    @Override
+    public Void result() {
+      return delegate.result();
+    }
+
+    @Override
+    public Throwable cause() {
+      return delegate.cause();
+    }
+
+    @Override
+    public boolean succeeded() {
+      return delegate.succeeded();
+    }
+
+    @Override
+    public boolean failed() {
+      return delegate.failed();
+    }
+
+    @Override
+    public <U> Future<U> compose(Function<? super Void, Future<U>> successMapper, Function<Throwable, Future<U>> failureMapper) {
+      return delegate.compose(successMapper, failureMapper);
+    }
+
+    @Override
+    public <U> Future<U> transform(Function<AsyncResult<Void>, Future<U>> mapper) {
+      return delegate.transform(mapper);
+    }
+
+    @Override
+    public <U> Future<Void> eventually(Supplier<Future<U>> mapper) {
+      return delegate.eventually(mapper);
+    }
+
+    @Override
+    public <U> Future<U> map(Function<? super Void, U> mapper) {
+      return delegate.map(mapper);
+    }
+
+    @Override
+    public <V> Future<V> map(V value) {
+      return delegate.map(value);
+    }
+
+    @Override
+    public Future<Void> otherwise(Function<Throwable, Void> mapper) {
+      return delegate.otherwise(mapper);
+    }
+
+    @Override
+    public Future<Void> otherwise(Void value) {
+      return delegate.otherwise(value);
+    }
+
+    @Override
+    public Future<Void> expecting(Expectation<? super Void> expectation) {
+      return delegate.expecting(expectation);
+    }
+
+    @Override
+    public Future<Void> timeout(long delay, TimeUnit unit) {
+      return delegate.timeout(delay, unit);
+    }
+  }
 }